Return empty list in case no dependencies are found #94

Reference: #94
Signed-off-by: Tushar Goel <tushar.goel.dav@gmail.com>

Author: TG1999

src/python_inspector/api.py

@@ -208,7 +208,7 @@ def resolve_dependencies(
     if not direct_dependencies:
         return Resolution(
             packages=[],
-            resolution={},
+            resolution=[],
             files=files,
         )
 

tests/data/setup/no-direct-dependencies-setup.py-expected.json

@@ -81,5 +81,5 @@
     }
   ],
   "packages": [],
-  "resolved_dependencies_graph": {}
+  "resolved_dependencies_graph": []
 }